Interlocking sheet piling



June 24, 1924. 1,498,778

(3. 5. BOARDMAN INTERLOCKING SHEET FILING Original Filed Nov. 2, 1921 a 4 1 j 5 a/ i INVENTOR ATTORNEY Patented June 24, 1924.

CHARLES SLAUSON IBOARDMAN, OF BUFFALO, NEW YORK.

INTERLOOKING SHEET FILING.

Application filed November 2, 1921,Serial No. 512,263. Renewed September 27, 1923.

To all whom it may concern:

Be it known that I, CHARLES S. BOARD- MAN, a citizen ofthe United States, residing at Buffalo, in the county of Erie and State of New York, have invented new and useful Improvements in Interlocking Sheet Piling, of which the following is a specification.

This invention relates to improvements in interlocking sheet piling and has for its object to produce a piling section capable of being successfully rolled and of a design combining many features which materially contribute to the production of a piling section superior in important respects to piling as heretofore rolled for commercial use. As hereinafter more fully described the piling sections of my present invention are of the type known as deep or wide sections and are peculiarly adapted to produce a wall wherein, to a substantially improved degree, the weight of metal disposed at a substantial distance from the neutral axis of the wall is increased so as to give the highest section modulus for the weight of metal employed and in consequence there is obtained a resulting wall materially improved with respect to the important factors of stiffness and strength in resisting lateral pressures.

An important use of interlocking steel sheet piling is in connection with reinforced or braced structures, for instance a cofferdam reinforced by interior bracing or a retaining wall braced at one side. In structures of this character the bracing members become a factor in the distribution of the pressures on the piling sections forming the wall and in my present improved design of piling section important advantages are obtained by properly designing the piling to cooperate with the bracing for obtaining high efficiency and particularly with respect to the water tightness of the resulting wall. To this end I have designed my improved section to have a deeply channelled web portion, intermediate of the interlocking members, of a form and arrangement providing for a large area of bearing contact with the supporting timbers and to form a section of substantial depth, or over all dimensions taken laterally, and wherein the relative arrangement of the interlocks are such that the channelled web portions of the adjacent interlocked sections are alternately disposed upon opposite sides of the neutral axis of the wall.

Associated with the aforesaid the interlocking flanges are of animproved arrangement wherein the thumb flange of the double interlock at each side of the piling is arranged at or to form the marginal edge of the piling section at each side thereof. This improved arrangement of the interlocking flanges results in additional economy in thedistribution of the metal of the piling in that it disposes the maximum metal of the web portions at the greater distance from the neutral axis of the assembled wall to further widen the wall and also obtains a relative positioning of the interlocking flanges which contributes materially to the water-tightness of the wall. The latter feature is particularly effective in the braced type of construction referred to in that the arrangement of the interlocks is such as to obtain the maximum degree of watertight value under the pressure imparted to the wall by the retained material acting upon the alternate and outwardly arched sections to force the interlocking flanges thereof into close contact with the coacting flanges of the intermediate and braced sections.

In further accordance with my invention a I have designed my improved piling with the flanges of the double interlocks relatively positioned and disposed to give the greatest value in resisting separation under longitudinal pull; in this regard the general arrangement of the interlocking flanges conform closely to that illustrated in my earlier Patent No. 923,110, of May 25, 1909, which has shown high efficiency in practice. An important characteristic of this type of double interlock is that the lines of contact between the interlocking flanges of the res ective sections are in a circular or cylindncal plane described from a common center from which the important advantage obtains that the water tight qualities are fully maintalned 1n angular and circular constructions. In addition thereto I preferably associate with the foregoing, improvements in the form of lnterlock providing supplemental sealing pockets or grooves adapted to retaln therein sand or silt to contribute to the water tightaccompanying illustrations in connection with which the reference characters of the description are applied to the correspond ing parts in the several views.

In the drawings: Fig. 1 is a plan view of a portion of a retaining wall formed of my improved piling of the features of my invention, employing a standard Lackawanna type of interlock.

Referring particularly to Figs. 1 and 2 of the drawing in which is shown the preferred form of piling embodying the improved neutral axis.

features of my invention, the web portion a is, as shown, formed of a deeply channeled section having the inclined laterally extended end portions or walls 1 connected by the central and relatively thickened longitudinally extending wall 2. The portions (1 have integrally rolled therewith the flanges of the interlock, as here shown comprising a thumb or hook flange 3 and a curved finger or guard flange 4 relatively arranged so as to form, or to enclose, the groove or pocket 5 adapted to receive freely therein the hook flange of an adjacent pile section. The interlock so formed is of the so called double interlock type as illustrated in prior patent to me No. 923,110 and dated May 25, 1909. The grooves or pockets 5 have a longitudinal mouth or opening 7 formed between the opposed surfaces of the hook flanges and the ends of the finger flanges which are somewhat less in width than the greatest internal width of the pockets and of lesser width than that of the hook portion of the thumb flange received within the pockets whereby the interlock is formed. From this arrangement it results that the piles or piling sections-can only be interlocked by vertically assembling and also that they can only be separated longitudinally of the wall by a sham of sufficient strength to distort both flanges on each of the two adjacent piles forming the interlock in question.

In accordance with my present invention the interlocking flanges are arranged whereby when the piling sections are interlocked the channelled web portions of the respective sections will be alternately disposed at opposite sides of the central longitudinal axis of the resulting wall thereby forming a wall of substantial width or depth in a lateral direction and with a substantial amount of metal at the maximum distance from the This produces a wall which will be of great strength in resisting the meagre lateral pressures of the retained material. As is readily understood, in deep cofler-dam and similar structures the lateral pressures to which the piling is subjected are very substantial requiring the use of internal whaling and bracing timbers for the purpose of sustaining the assembled structure.

A characteristic and important feature of the present invention resides in an improved arrangement and relation of the interlocking flanges with reference to the channelled web portions thereof from which advantages are obtained with respect to a more economical distribution of the metal to produce a wall of maximum width and which in the important field of braced installations will obtain an improved degree of water tightness in the interlocks.

For this purpose in my present design of piling the hook or thumb flanges of the interlocks are arranged at or to form the innermost marginal edges of the respective piling sections and the coacting finger or guard flanges are rolled to integrally project from the outer surfaces of the inclined portions 1 of the web in position intermediate of the hook flanges and the longitudinally extending or flattened web portion 2 of the section. By this arrangement upon interlocking of my improved piling section with a correspondingly formed pile, the respective sections are disposed at a relatively increased distance to each side of the longitudinal axis of the piling wall formed thereby and in consequence obtain the greatest value of the metal in resisting lateral stresses.

In the double interlock formed by the coaeting hook and guard flanges 3 and 4 the opposed inner engaging surface 8 of the hooked members are desirably arranged at an angle of approximately 45 or more with relation to the longitudinal axis whereby the pull longitudinally of the wall tending to separate the piling sections Wlll be opposed primarily by the hooked flanges but in a manner wherein they will be materially reinforced by the guard flanges 4; resulting in a particularly strong interlock as herelnbefore referred to."

As will be noted by reference to Figures 1 and 2 the interlocking flanges are designed to embody the essential features of the double interlock described and in addition may desirably be modified by the provision of supplemental longitudinally arranged channels or grooves 14 as shown. The channels or grooves 14 are rolled in the outer surface of the respective hooked flanges 1n the arrangement whereby their open sides Wlll be opposed to and closed by a portlon of the ad aCent section interlocked therewith. The arrangement thus provides for supplementary or additional pockets formed wlthin the interlock for the accumulation therein of sand and silt which will ofier additional re sistance to the seepage of water through the joints, and thereby contribute materially to the water tightness.

The advantages of my improved piling with respect to the water tight qualities thereof are obtained to the fullest degree in a braced wall of the type as illustrated in Figure 2. As therein shown one side of the pilin wall has bearing en agement upon suita 1e whaling or bearing timbers 9'by the engagement therewith of the web portion 2' of the alternate piling sections of which the wall is composed. As a result thereof the alternate sections which have their web portions 2 disposed toward the interior of the cofl'er-dam, or other structure, are reinforced against the pressures from the opposite side and may thus be considered as braced or rigid members. The intermediate sections or those having their web portions arranged to the opposlte or pressure side of the central longitudinal axis of the wall, as will be noted, have no bearing contact with the bracing members and are, therefore, subject to movement inwardly under the influence of the pressure of the retained material. In consequence the external pressures act upon these intermediate unbraced sections which may be said to be floating with respect to the braced sections, forcing these intermediate sections bodily inward into close contact with the interlocks of the braced sections thereby increasing the water tightness. A

close sealing contact within the interlocks is thus maintained by the external pressures to effect the closing of the main pockets 5, and the additionalsu plemental pockets 14 resulting in a wall 0 materially improved water tight value.

In Figure 3 I have illustrated a suitable modification embodying the features of my invention but wherein the hook flange conforms substantially to the simple contour illustrated in my prior patent referred to. This modified design as shown embodies the mproved feature of the hooked flanges bemg arranged at the inner marginal edge of the section as a result of which the interlock is such as to position theweb portions a to the maximum distance to each side of the central longitudinal axis of the wall or as may be expressed in other terms the interlock is effected with the minimum area of the cross-section disposed at the opposite side'of the neutral axis. In similar arrangement to the disclosure of Figures 1 and 2, the interlocks are arranged whereby the external pressures will act upon the intermediate sections to effect close sealing contact between the outer surface of the hook flanges and the inner surface of the guard flanges so that the pockets will be sealed by line contact at at least two points. Furthermore, as descr bed, the hooked flanges will resist longitudlnal separation in the manner to be properly reinforced by the guard flanges to obtain high efliciency.

The described piling section is thus adapted to produce an improved wall particularly with respect to'the important characteristic of resistance to lateral stresses and water tight qualities and while it will be readily understood that the resistance to lateral pressures is of vital importance in theasthe wall tearing apart. A further advantage inherent to my specific corelation of the interlocking flanges with the web portion. is that the transversely arranged or inclined portions 2 of the webs of the respective sections are positioned more closely in alignment than would obtain were the interlocking flanges reversed.

A further important feature of my improved piling as advantageously .related to the braced type of structure consists in the angularity of the inclined portions 1 of the piling web which are arranged to closely approximate a right angle with relation to the central, flattened and thickened portions 2 from which it results that the pressures are better sustained by the webs without tendency to flatten out.

Additional and important advantages are obtained incident to the specific type of interlock employed as a result of the arrangement of the interlocking flanges whereby the lines of contact within the interlock are in a circular or cylindrical plane described from a common center allowing for angularityin the assembling to produce irregular and circular constructions while maintaining the close line contact in the interlock. This arran ement is particularly advantageous in t e present design of section, in that should the angular portions 1 of the web be sprung or deflected slightly under extremal heav load the line of contact within the mterloc will move in this curved plane in a manner which will maintain the full water-tightness. The longitudinally extending portions 2 of the web are, as illustrated, of increased thickness relative to the angular portions 1. The cross sectional area of this flattened portion 2 of the web is specially designed to be of a thickness to properly balance the cross sectional areas or weight of metal in the interlocks considered in relation to the neutral axis of the individual section so as to produce the strongest and most economical section for the amount of metal used.

Having described my invention I claim:-

' marginal side edges thereof adapted to interlock with complemental interlocks of an adjacent section, the webs of the respective sections being of channelled formation and extending alternately to opposite sides of the central longitudinal axis, said interlocks being each composed of coacting hook and guard flanges adapted to form a socket to receive a hook flange of an adjacent section and the hook flanges of each of the interlocks being positioned to form the inner marginal edge of the piling section.

2. Steel sheet piling composed of interlocking sections, each section comprising a web having interlocks along the vertical marginal side edges thereof adapted to in terlock with complemental interlocks of an adjacent section, the webs of the respective sections being of channelled formation and extending alternately to opposite sides of the central longitudinal axis, said interlocks being each composed of coacting hook and guard flanges adapted to form a socket to receive a hook flange of an adjacent section and formed to have lines of contact in a cylindrical plane and the hook flanges of each of the interlocks being positioned to form the inner marginal edge of the piling section and the central portions of the web being flattened or longitudinally extended and of relatively enlarged cross section.

3. Sheet steel piling composed of interlocking sections, each section comprising a web having interlocks along the vertical marginal side edges thereof adapted to interlock with complemental interlocks of an adjacent section, the Webs of the respective sections being of channelled formation and extending alternately to opposite sides of the central longitudinal axis, said interlocks being each composedof coacting hook and guard flanges adapted to form a socket to receive a hook flange of an adjacent section and formed to provide lines of contact 1n a cylindrical plane described from a common center and the hook flanges of each of the interlocks being positioned to form the 1nner marginal edge of the piling section and having the engaging surface thereof opposing longitudinal separation arranged in angular relation of 45 or more to the central longitudinal axis of the wall.

4. Steel sheet piling composed of interlocking sections, each section comprising a web having interlocks along the vertical marginal side edges thereof adapted to in terlock with complemental interlocks of an adjacent section, the webs of the respective sections being of channelled formation and extending alternately to opposite sides of the central longitudinal axis, said interlocks being each composed of coacting hook and guard flanges adapted to form a socket to receive a hook flange of an adjacent section and the hook flanges of each of the interrename locks being positioned to form the inner marginal edge of the piling section and each of the hook flanges being formed at its outer side with a longitudinally extending groove having its open side opposed to and closed by the guard flange of the adjacent section interlocked therewith thereby to provide supplemental pockets in the interlock.

5. Steel sheet piling composed of interlocking sections, each section comprising a web having interlocks along the vertical marginal side edges thereof adapted to interlockwith complemental interlocks of an adjacent section, the webs of the respective sections being of channelled formation and extending alternately to opposite sides of the central longitudinal axis, said interlocks being each composed of coacting hook and guard flanges adapted to form a socket to receive a hook flange of an adjacent section and formed to provide lines of contact in a cylindrical plane and the hook flanges of each of the interlocks being positioned to form the inner marginal edge of the piling section and the central portions of the web being flattened or longitudinally extended and of relatively enlarged cross section, and each of the hook flanges being formed at its outer side with a longitudinally extending groove having its open side opposed to and closed by the guard flange of the adjacent section interlocked therewith thereby to provide supplemental pockets in the interlock.

6. Steel sheet piling composed of interlocking sections, each section comprising a Web having interlocks along the vertical marginal side edges thereof adapted to interlock with complemental interlocks of an adjacent section, the Webs of the respective sections being of channelled formation and extending alternately to opposite sides of the central longitudinal axis, said interlocks being each composed of coacting hook and guard flanges adapted to form a socket to receive ahook flange of an adjacent section and the hook flanges of each of the interlocks being positioned to form the inner marginalledge of the piling section, the central and longitudinally extending portions of the web being flattened and relatively thickened to have an enlarged cross sectional area ofa thickness substantially balancing the weight of metal of the interlocks in relation to the neutral axis of the section.

7. Steel sheet piling composed of interlocking sections, each section comprising a web having interlocks along the vertical marginal side edges thereof adapted to interlock with complemental interlocks of an' adjacent section, the Webs of the respective sections being of channelled formation and extending alternately to opposite sides of the central longitudinal axis, said interlocks being each composed of coacting hook and guard flanges adapted to form a socket to receive a hook flange of an adjacent section and formed to provide lines of contact in a cylindrical plane and the hook flanges of each of the interlocks being positioned to form theinner marginal edge of the piling section and having the engaging surface thereof opposing longitudinal separation arranged in angular relation of approximately to the central longitudinal axis of the wall and each of the hook flanges being formed at its outer side with a longitudinally extending groove having its open side opposed to and closed by the guard flange of the adjacent section interlocked therewith thereby to provide supplemental pockets in the interlock.

8. Steel sheet piling composed of interlocking sections, each section comprising a web having interlocks along the vertical marginal side edges thereof adapted to interlock with complemental interlocks of an adjacent section, the webs of the respective sections being of channelled formation and extending alternately to opposite sides of the central longitudinal axis, said interlocks being each composed of coacting hook and guard flanges adapted to form a socket to receive a hook flange of an adjacent section and the hook flanges of each of the interlocks being positioned to form the inner marginal edge of the piling section and having the engaging sur ace thereof opposing longitudinal separation arranged in angular relation of approximately 45 to the central longitudinal axis of the wall and each of the hook flanges being formed at its outer side with a longitudinally extending groove having its open side opposed to and closed by the guard flange of the adjacent section interlocked therewith thereby to provide supplemental pockets in the interlock, the central and longitudinally extending portions of the web being flattened and relatively thickened to have an enlarged cross sectional area substantially balancing the weight of metal of the interlocks in relation to the neutral axis of the section.

9. Steel sheet piling composed of inter locking sections, each section comprising a web having interlocks along the vertical marginal side edges thereof adapted to interlock with complemental interlocks of an adjacent section, the webs of the respective sections being of channelled formation and extending alternately to opposite sides of the central longitudinal axis, said interlocks being each composed ofcoacting hook and guard flanges adapted to form a socket to receive a hook flange of an adjacent-section and the hook flanges of each of the interlocks being positioned to form the inner marginal edge of the piling section, the cen' tral and longitudinally extending portions of the web being flattened and relatively thickened to have an enlarged crosssectional area of a thickness to substantially balance the Weight of metal of the interlocks'considered in relation to the neutral axis of the section, said angularly disposed end portions of the web being arranged in close approximation to a right angle with relation to the longitudinal axis of the section.

In testimony whereof I have signed. my name to this specification in the presence of two subscribing witnesses.

CHARLES SLAUSON BOARDMAN.

Witnesses:

THOMAS U. BUNTING, MARTIN W. LANTZ. 

